Refractory:

Apparent porosity & Bulk Density:Apparent porosity:

This is the amount of the total closed and open pores in the refractory materials inpercentage.The good refractory material should have a minimumporosity vale except in the case of the insulation bricks.Bulk Density:This is the ration of weight to the volume of the refractory materials in gram/cc.Thegood refractory material shouls have a high bulk density value for its betterperformance.Remove the outer layer of the bricks by sample cutting machine.Take the sample sizeoe 65x65x40mm and remove the moisture by putting them in air oven at 120 deg.C.Take out and allowed to cool.Take the dry weight in gm(D).Put the samples in thevessel containing water.Boil for about one hour.Take out and vipe out the excess waterby a wet cloth.Take the wet weight(W).The the suspended weight while the sample isimmersing in the water.(S)(W D)AP%

x 100(W-S)W

BD gm/cc =(W S)

Refractoriness under load:The resistance of the refractory materials

load,temperature,time etc.

under specified conditions of

Take the sample size of 50 mm diameter and 50 mm height(+ / - 0.5 mm) by a RULsample cutting machine.Calculate the area in cm2.Put the sample in the RUL testingmachine .Apply the of 2 kg per cm2.Set the dial gauge of 0.01 mm accuracy.Switch onthe RUL furnace to heta the sample.RUL temperature(t 0 C) is the temperature atwhich 0.3 mm deformatation take place ie. Measure the temperature when the dedle ofthe dial gauge is at 30th division after deformation taking place.Pyrometric cone equivalent:This is the resistance of the refractory material to soften during service temperature.

Take the composite sample of the refractory material in 150 micron size.Remove theiron by a magnet.Make the PCE sample of a regular tetrahedron of base in 8 mm andheight in 25 mm by using a PCE mould with the help of water and dextrose as abinder.Place the sample on a refractory flake along with the standard cone(Ortan/Sekhercone).Put the flake with the samples in a PCE furnace and raise the temperature.StandardSample

PCE temperature is the temperature at which the sample bend and its tip just tough theplane of the flake and can measure by a optical pyrometer. This is the comparison testand can compare with the standard sample. ie. if the standard bends first and thesample is intactthen the PCE value is + of the standard cone PCE number. If the sample bends firstand the standard is intact then the PCE value is minus of the standard cone number orif both the sample and standard are bend simultaneously then the PCE value is thesame value of the standard cone number.

Cold Crushing Strength:This is the ratio of the breaking load to the area in cm 2 of the refractor materials. Thegood refractory material should have high value of the cold crushing strength.Make the sample of size of 75 mm3 by sample cutting machine.Remove the moisturethe moisture by putting them in a air oven.After air cooling measure the area of thesample and place the sample in to the ccs machine with the cushion above and belowof the sample.Apply the load and note the crushing load in kg and calculate the CCSvalue.

Crushing loadCCS kg/cm2 =

kg/cm2Area of cross section.

Permanent linear change:The expansion of the refractory during service temperature in percentage is called aspermanent linear change.

Cut the sample of size 125x40 mm by a sample cutting machine and try in an air ovento remove the moisture. Measure the length of the specimen in mm. Place the samplein a PLC furnace and switch on the furnace. soak the samples in the specifiedtemperature for the specified period. Allow the samples to cool in the furnace itself.After cooling to the room temperature measure the final length of the specimens in thesame location and calculate the PLC value in %Initial length Final lengthPLC%

=.

X 100Initial length

War page:This is the bend of the refractory material. The good refractory material should freefrom war page.Place the war page gauge on the bigger area ie. On the surface of 230x115 mm2 of theladle brick and measure the bend/war page in mm.

P h y s i c a l:Tensile test:This is the ratio of the maximum load per area of the cross section on the tensile testpiece.Make the tensile sample as per IS-1608/latest.Measure the diameter of the sample andmake two dots apart 5 times of diameter of the test piece. Place the sample in to thetensile testing machine and apply the load. Note the yield load and the maximum loadand measure the reduced diameter of the broken sample.Calculate the tensilestrength.The sampling frequency shall be one per cast for axles and 1 for 1000,1 for500 and 1 foro 250 for Box-N,Carriage and loco wheels respectively.

Maximum loadTensile strength

Kg/mm2Area of cross section

Final length - Initial length

Elongation%=(GL-5.64 root A0 )

Initial length

Initial area Final area

Reduction area %

x 100Initial area

Micro grain size:This is the number of grains per square inch at 100x.Take the micro sample and grind wheel by a grinding machine. Use the emery papersof various grades from rough to fine and while changing the next emery paper thepolishing direction should be perpendicular to the previous paper. Use the diamondpaste for final polishing .Clean well by alcohol/dish paper and etch the polishedspecimen in 1:1 HCl.After drying check the micro grain size under metallurgicalmicroscope at 100 magnification. This is the comparison test and compare the grainsize with the standard chart as per IS-2853/latest.

Inclusion content:This also the comparison test and compare the inclusion rating with the stand chart asper IS-1463/latest and report as follows. Carry out the test before etching.

TypeSulphide(A type)Alumina(B type)Silicate(C type)Oxide(D type)

Thin

Thick

Macro examination.Take the vertical slice of wheel or axle. Mill it and heat in 1:1 HCl to the temperature75 - 80 degree centigrade for about half an hour. Take out the etched sample clean bywater and dry. Examine with the naked eye or low magnifying glass of less than10x.This also a comparison test and compare the macro piece with the standard chartas per Astm-381/latest.The etched sample should free from crack, non-metallicinclusion, flake, lap mark, segregation, pipe, pin holes, cavity and any other defects.

Hardness survey:Take a vertical slice of one inch thickness, mill it and take the indentation by 10 mmhardened steel ball in presence of 3000 kg load. Measure the diameter of theindentation by a Brinel microscope and find out the value from the chart of clculate thevalues by the following formulae.The sample frequency shall be one in 1000 for BoxN,one in 500 for Carriage and one in 250 for loco wheels.The hardness values shouldbe in desending in nature from flange to the hub of the wheel.

2PBHN =3.14xD(10 ( Root D2 - d2)Where PDd

LoadDiameter of the indenter anddiameter of the indentation

Closer test:This is the indication of the wheel contains a residual compressive stress afterquenching. Mark two points between 100 mm on the flange and the back rim. Take outa slice of one thickness of a vertical slice by two radial saw cuts in a Do all machine

and after taking out the slice for the hardness survey measurer the distance between thetwo points. The wheel should close and the minimum closer value should be +1 mm.Closer test of wheel: Puch 2 points apart 100mm on the flange Takeout a wheel slice of 1 thickness by radial saw cut machine(Do all) Take the final measurement and it shols be +1mm minium.

Hardness of wheel: Mill both sides of the vertical wheel slice taken out during closer test. Take BHN indentations by I gap fron flange to hub of the wheel by aBHN machine containing 10mm hardened steel ball&3000kgs load. The hardness value should decreasing in trend from flange to the hub.

Axle.Ultrasonic testing of axles.Purposes :To evaluate the quality of the axles by detecting the discontinuities which are harmfulto the axle service.Principle:Pass the ultrasonic sound in to the axle under test from one end face of better surfacefinishing of 3.2 micron. The sound rays will penetrate through out the axle and afterreaching the opposite end the sound rays will reflect back t o the home position by thereflection of the air medium.MethodEquipment usedNormal probefrequency

Low angle probe

CouplantStage of inspection

Pulse echo method

USD-15S,Khruatkrammer,German make or equivalent.PZT typeof 20-26 mm diameter and 2 2.5 MHzof Kruatkrammer,German make or eqivallent.Gun assembly contains 1.3,19.3&24.3 degree probes todetect the the discontinuities in body,up to inner wheelseat fillet and up to the outer wheel seat filletrespectively.Grease dissolved in oilSurface finish shall be better than 3.2 micron

Standardization:406

Probe

25381

Initial echo

Back wallFlaw echo (12.5%)

Place the normal probe just opposite to the 3.2 mm dia artifishal made flat bottom holeand adjust the gain to get 12.% of the flaw height. Not the gain and is called as FBHstandard gain.Standardization for Gun assembly:

Probe6mm saw cutGun assembly

Initial echowall

Flaw echo(75% height)

Back

Place the gun assembly on the standard axle containing 6 mm artifishal saw cut andadjust the flaw height to 75% and note the gain.It is the standard gain forGunassembly scanning.

Standardization for radial scanning(As per R-16/95):

2003.2252

150

Initial echo

Range =

Flaw echo(60%)

back wall

250 mm

Place the probe exactly opposite to the artificial flaw of 3.2 mm diameter and adjustthe gain to get 60% flaw height and note the gain. This is called as FBH standard gainfor radial scanning of R-16 / 95 axles.

Standardization for radial scanning(As per R-43/92):

2603.2252

150

Initial echo

Range =

Flaw echo(60%)

back wall

400 mm

Place the probe exactly opposite to the artificial flaw of 3.2 mm diameter and adjustthe gain to get 60% flaw height and note the gain. This is called as FBH standard gainfor radial scanning of R-43 / 92 axles.

Standardization for End End scanning: (As per R-1695&R-43/92)

406

Probe

253813.2(At mid radius)

Initial echo

Back wallFlaw echo (12.5%)

Place the normal probe just opposite to the 3.2 mm dia artificial made flat bottom holeand adjust the gain to get 12.5% of the flaw height. Note the gain and is called as FBHstandard gain.(All dimensions are in mm)

Length of DAC block in mm

3.2,6.4(Use for II zone also

as a first block)

II

533.4

6.4

660.4

6.4

787.4

6.4,9.5(Use for III zone

also as a first block

II

914.4

9.5

1041.4

9.5

1168.4

3.2,6.4,9.5

13

Visual inspection:Check the face, CTA, Journal, wheel seat and body of the axle visually by nakedeye/low magnifying lens etc. If the axle contains gouge mark, end crack of the defectsdue to the RWFs process make it as defective non-source(S).If the axle is gettingrejected ultrasonically made as UT rejected and if contains inclusion crack of anyother defects due to the manufacturer of the bloom make it as defective Source(S) andenter in LAN record.If the defect may go by further machining make it as others(O) orif it is free from any defects carry out the ultrasonic testing.Penetrability test:Clean the face of the axle and apply the couplant.Do the preliminary adjustments ofthe UFD and scan with normal probe.If the wack wall at FBH gain is mere than 25%further carry out the testing and the penetrability test is ok..If it is <25% mark it forRHTMore than two RHT is not permitted and the axle is rejected.Far end scanning:Clean the face of the axle and apply the couplant.Do the preliminary adjustments ofthe UFD and scan with normal probe&observe any signal between initial and backwall.If it is due to the shape/geometry of the axle it is ok.If it is due to flaw, reduce thegain in the setting FBH gain and if it is more the 12.5% amplitude height it is cause forrejection and enter in LAN as ut rejected.Testing by Gun assembly:Place the gun assembly on the axle face and rotate slowly at least twice in clock andanother twice in the anti clock directions and observed the ut screen. If there is no flawsignal the axle is ok and if there is a flaw signal with more than 75% of the amplitudeheight at FBH gain is a cause for the rejection.Manual radial scanning:Do the preliminary adjustments and apply the couplant on the axle laterally. Scan andif the axle is free from the flaw signal it is ok. Otherwise follow the following rejectionnorms for the radial scanning of the axle.a)

Flaw signal with more than 60% at FBH gain and more than 2 probe lengthon Journal & Wheel seat and more than three probe length on body is causefor rejection.b)If the distance between two isolated signals is lesser than 200 mm is acause for rejection.c)More than three isolated signals throughout the axle is a cause for rejection.d)Flaw signal with 60% of amplitude height provided the location is betweenand mod-radius & surface f the axle is cause for rejection.Manufacture of Box-N axle:Billet cutting:Cut the bloom in 975 +/- 5 mm by saw/gas cutting carefullyPreheating in RHW:-

14

Charge the billets in the RHW and heat to 1150 1200 deg C for about 6 hoursForging:Forge the preheated billets by long forging machineEnd cutting:Remove sufficient discards by gas cuttingNumber stamping:Stamp the serial number of the axle by automatic stamp punching machine in hotconditionIntermediate cooling:Allow the hot axle to cool to 200 - 250 deg. C through the intermediate cooling bedHeat treatment:Normalizing:Charge the cooled axles at 200 250 deg. C in to Normalizing furnace and heat to 840- 860 deg C for about 6 hours.Intermediate cooling:Allow the normalized axles to cool to 200 deg. C through the intermediated coolingbed.Tempering:Charge the air cooled axles to 200 deg. C in to the Tempering furnace at thetemperature of 550 - 640 deg. C for about 8 hours 45 minutes.Air cooling:After tempering allow the tempered axles to air cool for about 24 hours.Lab. Test:Take two samples of size 250x25x25 mm size from the center portion of the prolongedjournal portion of the heat treated axle and conduct all the required tests to conformfollowing requirements as per R-16-/1995.Physical properties:-

Requirements as per R16/95

Machining of the axle:a.

Cup turn,end mill and make the lathe center bore.Number stamping:Punch the serial No. and Cast No. of the axle manually on the axle face.Ultrasonic testing:Scan the axle ultrasonically thoroughly and if the axle is passing allow to furthermachining by putting the UT stamp on the axle number face.

16

Further machining:b.Rough turn the axlec.Semi finishing of the axle except bodyd.Body finishinge.Finishing of the axle except bodyf.Drilling, tapping and recentering of the axleg.Furnishing of wheel seath.Centreless grinding of journal, dust guard etc.Magnetic particle testing of axle:Conduct the MPT of the axle and if it is passed allow the passed axle for pressing byputting the MPT stamp on the axle face opposite to the UT stamp.

Magnetic Particle Testing of axle:(MPT)

Equipment used:Magnaflux,USA make of DH 5455 model.Current used:Half wave DC for coil&Contact magnetizationAC for DemagnetisationCurrent used forCoil magnetization = 1200 Amps.Contact magnetization = 1800 Amps.Demagnetization = 3000 Amps.Bath oil = MX-MG Carrier Oil-II supplied by M/s.ITW Signode,Hyderabad.MPT Powder = Magnaflux-14A supplied by M/s.ITW Signode,Hydreabad.Amount of powder per litre = 1.25 gram/litre.Concentration of the bath = 0.2 - 0.30 ml/100 ml after half an hour.Watt of the UV lamp = 100 watt.Intensity of the UV lamp = 525 micro watt/centimeter square.Principle:Magnetize the axle under test.Magnetic force of lines will develop.Spray the bath containing containingiron particle coated with flourescent material.If there is a defect,the magnetic force of lines will leaki.e. leakage of magnetic flux arround the defect and attract more particle around the defect and can seenunder UV lamp.Coil magnetization:Place the coil over wheel seat and pass the current through the coil to develop longitudinal field.Spray the.bath and after few seconds inspect under UV lamp to detect the verticle discontinuities.The discontinuitywill develop polority and will attract more powder arround the defect and can seen under UV lamp.If the defectmay go by re work mark for rework.Contact magnetization:Press the contact pad and pass the current through the axle to develop circular magnetic field to detect thelongitidinal discontinuities.Spray the bath and inspect under UV lamp as above.Demagnetization:Press the contact pad and pass the AC current through the axle to demagnetize the magnetized axle.Theresidual magnetic field shall be plu or minus 5 gauss.Imperfections not permisciple:1. Any type of verticle,circumferential discontinuities any where on the axle not permitted.2 Any type of discontinuities on the fillet not permitted.

17

Imperfection permiciple:Journal:

Heat diagram of Box-N axle:

Heat diagram of BGD axle:

18

Iron - Carbon System

1600LiquidDelta iron1539Delta iron + Liquid0.53%Austenite

0.08%

Liquid+Cemintite

1490Austenite+Liquid1400Liquid+Austenite

Austenite+Delta

Temper

1146 oC

Austenite+Ferrite910768

Austenite+Aus+ LedeburiteCemin+titeCemintite

Cemintite+Ledeburite727 oC

19

Iron-Carbon System:ture

0.02%

FerritePearlite +Ferrite

Pearli Pearlt ite +e Fe3C

Pearlite+Transformed Ledeburite +Cementite

0.824.3SteelCast IronHypoHyperHypoEutectoidEutectoid Euectic

Cemintite+Ledeburite

6.67HyperEutectic

Carbon% wt

Fe-C system is a graphic representation of various transformation of carbon % weight at various

temperatures.Phases:Ferrite:It is an interistial solid solution in which carbon in BCC iron .The maximum solubility is 0.02%maximum at 227 degree centigrade. It exists from 910 degree centigrade to minus 273 degree centigrade.Austenite:It is an interstitial solid solution of carbon in FCC iron. The maximum solibility is 2.1 % at 1146degree centigrade.Delta iron:It is an interstitial solid solution of carbon in BCC iron. The maximum solibility is 0.08 %at 1400 degree centigrade.It is from 1539 degree centigrade which is the melting point of iron to 1400 degree centigrade.Pearlite:This an alternative arrangement of parallel plates of ferrite and cemintiteCemintite:It is an intermetalic compound represented by the formula Fe3O4.the structure isorthorhombic and the number ofatom is 25% but the C weight % is 6.67.Hence after 6.67% of carbon the Fe-c system isnot extended.Transformations:

Liquid iron will become austenite and cemitite on cooling at 1146 degree centigradetemperature.3.Eutectic reaction:ReactionStructureC% wt.

AusteniteFCC0.80

FerrriteBCC0.02

CemintiteOrthorhombic6.67

Critical temperatures:These are the temperatures at which various transformations tking place and are as follows.1.Gama iron will become ferrite and cemintite on cooling at 727 degree centigrate and represenedby the symbols A,c,r etc.,On slow cooling Ac1=Acr=727 degree centigrade.On normal cooling there is thermal hysterisis and Ac1>Acr.2.The next higher is curie temperature of ferrite iron & represented by the symbol A2 and is 768degree centigrade at whichfrrrite will undergo magnetic transition from ferro to para magnetic stage.3.The temperature corresponds to the phases Gama+ferrite/gama iron is A3 and it is steeperdegreses from 910 degreecentigrade to 727 degree centigrade.Unlike A1 this is function of carbon % weight.4.The temperature corresponds to the phase Gama iron+cemintite/gama iron is ACM and is increasedfrom 727 to 1146 degreecentigrades.This also a function of carbon % weight.5.The curie temperature of ferrite is A0 and is 210 degree centigrade.Micro structure of steel:

21

1.Eutectiod steel:The structure is pearlite and the chemical composition is '0.80% C weight. The amount of ferrite &cementite can be calculatedBy lever rule and is as follows.

ON LINE ULTRASONIC TESTING OF CAST STEEL WHEELS MANUFACTURED

AT RWFIntroductionAll the cast wheels shall be ultrasonically tested with minimum of 6 transducers in twodirections (radially and axially) through rim section in accordance with IRS R-19/1993(Part III). The Calibration reference standard and rejection level of each wheel design isestablished by making test set-up wheel. Procedure for ultrasonic testing of cast steelwheels are followed as laid down in the relevant specification.Standardization of Ultrasonic testing system is carried out in the beginning of each shiftor whenever there is a break down or any change of component in on line system orchange in wheel design under process.The custom built ultrasonic system is in compliment with the production process to detectall possible casting defects in rim section of the wheel.Ultrasonic scanning systemIn casting of wheels by controlled pressure pouring technique, defects like shrinkageporosity, gas holes etc., which occur during solidification within the rim section. In RWFthe ultrasonic testing methodology employed is automatic on line immersion technique inwater medium incorporating 6 transducers connected to a microprocessor based multichannel computer controlled scanning system.

diameter are employed. Each transducer is identified as 1A, 2A, 3A, 1B, 2B & 3B. Transducer 1A(2.25MHz) is focused axially closer to tread for detecting defectslike gas holes below the front rim face and closer to tread. Transducer 1B(2.25MHz) is adjusted axially for detecting gas holes that mayoccur below the front rim face farther away from tread and for cavities below thesprue area. Transducer 2A(5.0MHz) is adjusted radially located below the tread for detectingdefects at the central line. Transducer 2B(5.0MHz) is focused radially located below the tread for detectingdefects at 1/8 away from the central line towards back rim. Transducer 3A(5.0MHz) is adjusted axially through front rim for detectingdefects at the central line. Transducer 3B(5.0MHz) is adjusted radially located below the tread for detectingdefects below the sprue.All above 6 transducers are assembled in manipulator probe assembly immersed in tankcontaining continuous flow of water.Test Set UpAn ultrasonic standard test wheel of each design is fabricated by saw cutting the rimcross-section and artificial reference holes of 1/8dia length are introduced atshrinkage co-ordinates of the respective locations. Slices are welded back to match theoriginal profile of the wheel.The above wheel is used as a standard-set-up-wheel for setting up probes so as to achievemaximum response from the artificially drilled holes in the wheel rim.Sensitivity of the equipment is set by using UT standard manufactured from the samedesign wheel with 1/8 flat bottom hole, which will not be disturbed during the normaltesting process.Testing SystemRWF has employed microprocessor based computer controlled automatic on-lineultrasonic system, which consists of basic ultrasonic machine, multiplxer, oscilloscope,and computer with dedicated custom built software. The whole system is inter-linkedwith PLC for communication and control. The Speed of the wheel is kept at 4 rpm andminimum of 2 revolutions for a complete test cycle is ensured for every wheel. All thetesting parameters are displayed on screen and reference location is measured by the helpof an encoder. During the test, any signal from the defect location exceeding the set levelwill be indicated on the screen as REJECTED and wheel stops automatically.Inspectors ensure the defect & location manually and send the wheel to the scrap line.28

Other wise, wheel automatically deemed as PASSED by the system and moves forfurther processing. Ultrasonic status of the all the wheels tested is entered into the LANfor record.Equipment in usePresently RWF is using 2 customized ultrasonic testing system designed and supplied byM/s ULTRASONIC SCIENCES LIMITEDUnit 4-Spring Lakes Industrial EstateGU-12 4 UH, Dead brook lane, AldershotHampshire, ENGLANDTel: +44(0) 1252350550Fax: +44(0) 1252350445E-mail:info@ultrasonic-sciences.co.ukWebsite:http://www.ultrasonic-sciences.co.uk

Ferro alloy calculation:

Qty to be added=

For any alloy =

Points to be added x Tonnage of liquid metal x 10

-------------------------------------------------------------Efficiency of alloy

To a clean mixing tank add 8 gallons of water. A permanent mark shall bemade on a rodthat relates 8 known gallons of water to a certain depth in the mixing tank. Turn mixeron.It is imperative that the mixing tank be thoroughly clean and completely empty.Absolutely no spray mixture should remain in the tank from a previous batch.

b)

Add 1 gallon of water to the specified mixing bucket. Turn waring blender on and add 1bag (22.7 grams) of CMC powder slowly and uniformly to the water, while the agitator iscontinuously in operation. Mix fore a minimum of 2 minutes, making sure that the CMCis completely dissolved and free of lumps. Add this mixture to the larger mixing tank.

c)

Repeat the above operation (b), using one gallon of water and 22.7 grams of CMC.

d)

To the appropriate mixing bucket add 1 gallon of water and 1 bag (152 grams) ofVeegum-T, Mix for a minimum of 1 minute or until the Veegum-T is completelydissolved and free of lumps.

e)

Repeat the above operation (d), using one gallon of water and 1 bag (152 grams) ofVeegum T.f)Repeat the above operation (d), using one gallon of water and 1 bag (152grams) of Veegum-T.

g)

After all the premixed CMC and Veegum-T has been added to the large mixing tank, wait5 additional minutes before adding the fused silica. Each of the two 50 lb. Bags shall beadded separately and not until the prior bag has gone into solution. The lightening mixermust be in operation at all times. Any paper from the bags that falls into the tank must beremoved.h)After above solution has been mixed for 5 minutes, add 120 ml offormaldehyde.30

i)With the Baume instrument, measure the density of the spraymixture. Adjust the consistency of the solution to 35O - 40O Baume. (Baume maybe different from plant to plant depending non gun distance from mold and othervariables. This difference shall be verified through the Operating Department). Ifthe Baume is too high, add water slowly, and carefully bring down the Baumewithin limits. If the Baume is too low, add Fused Silica slowly and carefully bringup the Baume within limits. Determine the proper amount of water to add to themixing tank (in part (a)) in order to obtain a consistent Baume on the final spraymixtures from batch to batch.j) The Baume shall be recorded on the 302s for the molds being sprayed.6B. Mold Spray mix 100 lb. Batch 36O Baume (Alternate method).Ingredients:CMC 0.1% OF THE WEIGHT OF fuses Silica, 1 bag weighing 45.4 grams.Veegum T 1.0% of the weight of Fused Silica, 1 bag weighing 454 grams.30 Micron Fuses Silica 100 lbs. (45,400 gms).Formaldehyde 120 ml (optional depending on

bacteria levels).

Hot water used with initial CMC and Veegum Solution.

Mixing Instructions:a) To a large clean mixing tank add 7 gallons of water. A permanent mark shall be made onrod that relates 7 known gallons of water to a certain depth in the mixing tank. Turnmixer on.It is imperative that the mixing tank be thoroughly clean and completely empty.Absolutely no spray mixtures should remain in the tank from a previous hatch.a)Add 3 gallons of water to a mixing bucket (Detail-D) or sufficient water to bringwater level upto a known marker. Turn Waring Blender on and add 1 bag (45.4 grams) ofCMC powder slowly and uniformly to the water while the agitator is continuously inoperation. Mix for a minimum of 5 minutes making sure that the CMC is completelydissolved and free of lumps. Add this mixture to the larger mixing tank.a)To the mixing bucket add 3 gallons of water (or sufficient water to bring waterlevel upto a known marker) and add 1 bag (456 grams) of Veegum-T. Mix for aminimum of 5 minutes or until the veegum-T is completely dissolved and free of lumps.Again the mixer should be turning prior to adding the Veegum-T in a slow and uniformmanner. Add this mixture to the larger mixing tank.a)After all the premixed CMC and Veegum-T have been added to the large mixing tank,wait 5 additional minutes before adding the Fused Silica. Each of the two 50 lb. Bagsshall be added separately and not until the prior bag has gone into solution. The lightningmixer must be in operation at all times. Any paper from the bags that fall into the tankmust be removed.31

a)

After above solution has mixed for 5 minutes, add 120 ml of formaldehyde.

b) With Baume instrument, measure the density of the spray mixtures. Adjustthe consistency of the solution to 35O - 40O Baume. (Baume may be differentfrom plant to plant depending on gun distance from mold and other variables.This difference shall be verified through the Operating Department). If theBaume is too high, add water slowly and carefully bring down the Baumewithin limits. If the Baume is too low, add Fused Silica slowly and carefullybring up the Baume within limits. Determine the proper amount of water toadd to the mixing tank (in part (a)) in order to obtain a consistent Baume onthe final spray mixture from batch to batch.c)

The Baume shall be recorded on the 302s for the molds being sprayed.

7A.

Mold Spray mix 125 lb Batch 36O Baume

CMC 0.1% OF THE WEIGHT OF fuses Silica, 2 bags

weighing 28.4 grams.Veegum T 1.0% of the weight of Fused Silica, 3 bagsweighing 190.0 grams each.30 Micron Fuses Silica 125 lbs. (56,800 gms).Formaldehyde 150 ml (optional depending on bacterialevels).Hot water used with initial CMC and Veegum Solution.Mixing Instructions:a)To a large clean mixing tank add 11.25gallons of water. Apermanent mark shall be made on rod that relates 11.25 knowngallons of water to a certain depth in the mixing tank. Turn mixeron.It is imperative that the mixing tank be thoroughly clean and completelyempty. Absolutely no spray mixtures should remain in the tank from aprevious hatch.a)

Add 1 gallons of water to a appropriate mixing bucket. Turn Waring Blender

on and add 1 bag (28.4 grams) of CMC powder slowly and uniformly to thewater while the agitator is continuously in operation. Mix for a minimum of 2minutes making sure that the CMC is completely dissolved and free of lumps.Add this mixture to the larger mixing tank.

c) Repeat the above operation (b), using 1 gallon of water and 1 bag (28.4 grams) ofCMC.d) To the small mixing bucket add 1 gallons of water and add1 bag ( 190.0 grams) of Veegum-T. Mix for a minimum of 132

minute or until the veegum-T is completely dissolved and free of

lumps. Again the mixer should be turning prior to adding theVeegum-T in a slow and uniform manner. Add this mixture to thelarger mixing tank.a)

b) Repeat operation (d), using 1 gallon of water and 1 bag (190.0 grams) ofVeegum-T.g)After all the premixed CMC and Veegum-T havebeen added to the large mixing tank, wait 5 additional minutesbefore adding the Fused Silica. Each of the two 50 lb. Bags shallbe added separately and not until the prior bag has gone intosolution. The lightning mixer must be in operation at all times.Any paper from the bags that fall into the tank must be removed.d) After above solution has mixed for 5 minutes, add 150 ml of formaldehyde.e)

With Baume instrument, measure the density of the spray mixtures. Adjustthe consistency of the solution to 35O - 40O Baume. (Baume may be differentfrom plant to plant depending on gun distance from mold and other variables.This difference shall be verified through the Operating Department). If theBaume is too high, add water slowly and carefully bring down the Baumewithin limits. If the Baume is too low, add Fused Silica slowly and carefullybring up the Baume within limits. Determine the proper amount of water toadd to the mixing tank (in part (a)) in order to obtain a consistent Baume onthe final spray mixture from batch to batch.

f)

The Baume shall be recorded on the 302s for the molds being sprayed.

33

7B.

Mold Spray mix 125 lb Batch 36O Baume

CMC 0.1% OF THE WEIGHT OF fuses Silica, 2 bags

weighing 56.8 grams.Veegum T 1.0% of the weight of Fused Silica, 3 bagsweighing 568 grams each.30 Micron Fuses Silica 125 lbs. (56,800 gms).Formaldehyde 150 ml (optional depending on bacterialevels).Hot water used with initial CMC and Veegum Solution.Mixing Instructions:a)To a large clean mixing tank add 10.25 gallons of water. Apermanent mark shall be made on rod that relates 10.25 knowngallons of water to a certain depth in the mixing tank. Turn mixeron.It is imperative that the mixing tank be thoroughly clean and completelyempty. Absolutely no spray mixtures should remain in the tank from aprevious hatch.b)Add 1 gallons of water to a appropriate mixing bucket(Detail-D) or sufficient water to bring water level upto a knownmarker. Turn Waring Blender on and add 1 bag (56.8 grams) ofCMC powder slowly and uniformly to the water while the agitatoris continuously in operation. Mix for a minimum of 2 minutesmaking sure that the CMC is completely dissolved and free oflumps. Add this mixture to the larger mixing tank.c) To the mixing bucket add 3 gallonss of water are sufficientwater to bring water level upto a known marker)and add 1 bag (568.0 grams) of Veegum-T. Mix for a minimum of 5 minute oruntil the veegum-T is completely dissolved and free of lumps.Again the mixer should be turning prior to adding the Veegum-T ina slow and uniform manner. Add this mixture to the larger mixingtank.d)After all the premixed CMC and Veegum-T havebeen added to the large mixing tank, wait 5 additional minutesbefore adding the Fused Silica. Each of the two 50 lb. Bags shallbe added separately and not until the prior bag has gone intosolution. The lightning mixer must be in operation at all times.Any paper from the bags that fall into the tank must be removed.e)

After above solution has mixed for 5 minutes, add 150 ml of formaldehyde.

34

f)With Baume instrument, measure the density of the spray mixtures. Adjust theconsistency of the solution to 35O - 40O Baume. (Baume may be different from plant to plantdepending on gun distance from mold and other variables. This difference shall be verifiedthrough the Operating Department). If the Baume is too high, add water slowly and carefullybring down the Baume within limits. If the Baume is too low, add Fused Silica slowly andcarefully bring up the Baume within limits. Determine the proper amount of water to add to themixing tank (in part (a)) in order to obtain a consistent Baume on the final spray mixture frombatch to batch.g)

The Baume shall be recorded on the 302s for the molds being sprayed.

35

8A.

Mold Spray mix 200 lb Batch 36O Baume

Ingredients:CMC 0.1% OF THE WEIGHT OF fuses Silica, 4 bags weighing 22.7 grams.Veegum T 1.0% of the weight of Fused Silica, 3 bags weighing 152 grams each.30 Micron Fuses Silica 4 bags weighing 50 lbs each or a total weight of 200 lbs. (90,800 gms).Formaldehyde 240 ml (optional depending on bacteria levels).Hot water used with initial CMC and Veegum Solution.Mixing Instructions:a)To a large clean mixing tank add 16 gallons of water. A permanent mark shall be madeon rod that relates 16 known gallons of water to a certain depth in the mixing tank. Turn mixeron.It is imperative that the mixing tank be thoroughly clean and completely empty. Absolutely nospray mixtures should remain in the tank from a previous hatch.b)Add 1 gallons of water to a appropriate mixing bucket. Turn Waring Blender on and add1 bag (22.7 grams) of CMC powder slowly and uniformly to the water while the agitator iscontinuously in operation. Mix for a minimum of 2 minutes making sure that the CMC iscompletely dissolved and free of lumps. Add this mixture to the larger mixing tanks.b)

Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.b)

Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.

c)

Repeat the above operation (b), using 1 gallon of water and 22.7 grams of CMC.

d)

To the appropriate mixing bucket add 1 gallons of water and add 1 bag ( 152.0grams) of Veegum-T. Mix for a minimum of 1 minute or until the veegum-T iscompletely dissolved and free of lumps.c)

l)After all the premixed CMC and Veegum-T havebeen added to the large mixing tank, wait 5 additional minutesbefore adding the Fused Silica. Each of the two 50 lb. Bags shallbe added separately and not until the prior bag has gone intosolution. The lightning mixer must be in operation at all times.Any paper from the bags that fall into the tank must be removed.m)After above solution has mixed for 5 minutes, add240 ml of formaldehyde.n)With Baume instrument, measure the density of thespray mixtures. Adjust the consistency of the solution to 35O - 40OBaume. (Baume may be different from plant to plant depending ongun distance from mold and other variables. This difference shallbe verified through the Operating Department). If the Baume is toohigh, add water slowly and carefully bring down the Baume withinlimits. If the Baume is too low, add Fused Silica slowly andcarefully bring up the Baume within limits. Determine the properamount of water to add to the mixing tank (in part (a)) in order toobtain a consistent Baume on the final spray mixture from batch tobatch.o)

8B.

The Baume shall be recorded on the 302s for the molds being sprayed.

Mold Spray mix 200 lb Batch 36O Baume(Alternate method)

IngredientsCMC 0.1% OF THE WEIGHT OF fuses Silica, 4 bagsweighing 45.4 grams.Veegum T 1.0% of the weight of Fused Silica, 2 bagsweighing 454 grams each.30 Micron Fuses Silica 4 bags weighing 50 lbs each or a totalweight of 200 lbs. (90,800 gms).Formaldehyde 240 ml (optional depending on bacterialevels).Hot water used with initial CMC and Veegum Solution.Mixing Instructions:a)To a large clean mixing tank add 16 gallons of water. Apermanent mark shall be made on rod that relates 14 known gallonsof water to a certain depth in the mixing tank. Turn mixer on.It is imperative that the mixing tank be thoroughly clean and completelyempty. Absolutely no spray mixtures should remain in the tank from aprevious hatch.37

a)

b)Add 3 gallons of water to a appropriate mixing bucket orsufficient water to bring water level upto a known marker. TurnWaring Blender on and add 1 bag (45.5 grams) of CMC powderslowly and uniformly to the water while the agitator is continuouslyin operation. Mix for a minimum of 5 minutes making sure that theCMC is completely dissolved and free of lumps. Add this mixtureto the larger mixing tank.Repeat the above operation (b), using 1 gallon of water and 45.5 grams of CMC.d) To the mixing bucket add 3 gallons of water or sufficientwater to bring water level upto a known maker and add 1 bag (454.0 grams) of Veegum-T. Mix for a minimum of 1 minute oruntil the veegum-T is completely dissolved and free of lumps.Again the mixer should be turning in a slow and uniform mannerprior to adding the Veegun-T. Add this mixture to the largermixing tank.e)Repeat operation (f), using 1 gallon of water and 1 bag(152.0 grams) of Veegum-T.f)After all the premixed CMC and Veegum-T have beenadded to the large mixing tank, wait 5 additional minutes beforeadding the Fused Silica. Each of the two 50 lb. Bags shall be addedseparately and not until the prior bag has gone into solution. Thelightning mixer must be in operation at all times. Any paper fromthe bags that fall into the tank must be removed.g)After above solution has mixed for 5 minutes, add 240 mlof formaldehyde.h)With Baume instrument, measure the density of the spraymixtures. Adjust the consistency of the solution to 35O - 40OBaume. (Baume may be different from plant to plant depending ongun distance from mold and other variables. This difference shallbe verified through the Operating Department). If the Baume is toohigh, add water slowly and carefully bring down the Baume withinlimits. If the Baume is too low, add Fused Silica slowly andcarefully bring up the Baume within limits. Determine the properamount of water to add to the mixing tank (in part (a)) in order toobtain a consistent Baume on the final spray mixture from batch tobatch.

i)

The Baume shall be recorded on the 302s for the molds being sprayed.

38

2.

Typical Mixes to Obtain 29-33 Baume with 15 Micron Min-U-Sil.

Total QuantitiesGalsGRSWaterCMC

GRSVeegum

MLFORMALDEHYDE

1020304050

2.03.85.77.60.5

4.540.0913.618.1622.70

45.691.2136.8182.4228.0

1224364860

Order of AdditionGalsGRSWaterCMCIn+tank1 Gal.Water04.541.89.083.713.625.618.166.522.70

Heat treatment of axle:

The process involving heating&cooling to egt the desired properties suitable forserviceby changing the structure,composition etc.Stages of heat treament:1. Heating to the required temperature2. Holding(Soaking) at this temperature for a period of time to attainuniform temperature throughout the section.3. Cooling the steel at specified rate.

Normalizing

Existing structure and

Existingstructure andproperties of

properties of

steel

steel

Quenching

Tempering

Principle of heat treatment

Aircooling

Normalizing:It is the process of heating the steel to above the upper critical temperature followed by cooling inair.NormalizingAustenite910

TemperatureO

723

Ferrite +Pearlite

Pearlite +Cemintite0.8

C% wtPurpose:1. To relieve the internal stress2. To refine the grain structure41

Time in hrs(Cycle time x capacity

Tempering:Process of heating the axle to a temperature below lower critical temperature followed by aircooling.Purpose:1.2.3.4.

To reduce the thermal stress

To stabilize the structure of the axleTo reduce the brittleness andTo increase the toughness&ductibility.

Austenite910

TemperatureO

723640

Tempering

550

0.8

C% wt

Temperature&time of TF:ZonesPre heatingMain heating

Temperature in o CRequiredSet550-640610610-640610

Time (Cycle time x capacity of the

furnace)2 hrs 55 min.2 hrs 55 min.42

Soaking

610-640

610

2 hrs 55 min

Quenching:The process of heating the axles to austenite phase followed by sudden cooling in polymerquenchant which is echo friendly for about half an hour.Purpose of hardening followed by tempering :1.To develop high hardness, wear resistance and2.To improve the strength and toughness

Measurement of SPM of ambient air quality:

Take the initial weight of the moisture free filter paper in gm

Place the paper on the air sampler,set the time for 24 hours and switch on.

c)

Note the flow rate in M3 per min.

d)

Calculate the volume of air sample(V) m3/Min

V

e)

Flow rate x Time in hours(24 hrs)

Take the final weight of the filter paper in gm

Wt of dustx 106

SPM =

m / m3

Eg)FWtIWt

==

4.1970 gm2.8627 gm

Wt of the dust =

1.3343 gm

Flow rate

1.435 m3 / min.

Tsampling

24 x 60 Min.

1.435 x 24 x 60 M3

1.3343SPM

x 1061.435 x 24 x 60

SPM

645.71 m / m3

45

Manufacturing of Wheel:Furnace used:High power basic direct electric arc furnace.The charge is melted by the heat produced by the arcby passing high power electric current through the graphite electrodes.The charge is loaded asheavy,medium&light scraps in bottom,middle&top of the furnace respectively.Charge:The raw material contains axle end cuts, risers, wheel cuts, medium scraps like sleeper, steelplate,rods,buffes,spikes,keys etc.,borings,shereded scraps etc.The weight od each in the buckectis as follows.Sl.No.

Type of scraps

Number of magnets

1234567

Axle end cuts

Melting:The scrap is melted under a basic oxidizing slag consisting of lime stone and mill scalesproviding cutting os scrap / collapses of bridges by O2 lancing..Consequently the Si,Mn&Ppresent are observed in to the basic oxidizing slag(Black) and when the process is completed,theslag is completely removed without drain of steel melt.Take sample and send to spectro foranalysis. The oxidation reaction reactions are:

2FeO

Si

SiO2

FeO

Mn

MnO

FeO

SiO2

FeO.SiO2

MnO

SiO2

MnO.SiO2

5FeO

2P

5Fe

3FeO

P 2 O5

(FeO)3.P2O5

(FeO)3.P2O5

3CaO =

3FeO +

2Fe

P2O5

(CaO)3 . P2O5

In the next stage new slag is formed by adding reducing slag mixture to deoxidize the bath.Deozidation occurs due to the unoxidized Mn left during the first stage.Lime reacts with C toform CaS which will further deoxidize and fix the S as CaS.The reactions are:FeO

Mn

Fe

MnO46

3C+3FeO +3MnO +

CaO =CaC2 =CaC2 =

CaC2 +3Fe+3Mn +

COCaOCaO

++

2CO2CO

Sulphur present in the steel as FeS&MnS.and eliminated in the following way.

3FeS3MnSFeSMnS

++++

CaC2CaC2CC

++++

2CaO2 CaOCaOCaO

====

3Fe3MnFeMn

++++

2CO2COCOCO

++++

3CaS3CaSCaSCaS

CaS is insoluble in steel and will join with slag(White) and CO will maintain reducingatmosphere in the furnace.Add Fe-Mn/Si-Mn to pick up the Mn containt in the bath(0.35 0.45%).Decarboration/recorporation may done by O2 lancing/by adding graphite powder as perthe spectr sample result.Stir the bath and maintain the temperature as 1640 1650 oC and take thepre tap sample.After stirring the bath again take the 2nd pretap sample within 2 -3 minutes.Raisethe temperature to 1680 - 1740 and tap the metal bath by opening the tap hole through the spoutin to the pre heated ladle containing calculated quantity of Graphite powder,Ferro-Silicon,FerroManganese/Silico-Manganese as per the spectro sample result.Transfer the ladle with the molten metal in to the slaggoff station and remove the slag from thecenter by slag coated metallic rabble through the lip of the ladle.Take slagoff sample for spectroanalysis and transfer the mladle in to John-mohr pressure pit.Measure the temperature by the TCtip and when the temperature is 1620 oC add Al star of weight 450 gms each in to the bottom ofthe ladle with the help of metallic rod to kill the steel.Take samples for ladle anslysis & H2&N2measurement by spectro&Leco gas determinater respectively.Casting:Start the casting at 1610 - 1520 oC by bottom pressure pouring technique after closing thepressure pit by the lid containing preheated ceramic pouring tube at its center by using graphitemould(Assembled Cope&Drag moulds).When the molten metal touch the probe inserted in oneof the riser the pressure will drop and simultaneously the clay graphite stopper head will close theentrance of the molten metal to prevent the run back. Add sufficient quantity of rice hull toprevent the dropping of temperature and transfer the mould for solidification.Splitting:After calculated time(10-12 Min.)split the mould using the split grain.If dropping of metal isobserved increase the solidification time of reduce the solidification time if the risers are notfallen during the splitting.Pass the hot wheels through the hot wheel kiln foe further hotprocessing.Sprue Wash:Wash the protruded sprue by copper cotted electrode of one inch thichickness by using thecurrent of 1200-1800 Amps and minimum temperature of the sprue wash shall be of 380 oC toprevent the sprue crack formation.Number stamping:Stamp the correct number of the heat on the back hub face by automatic number stampingmaching.Hub cutting:Make the hub bore by oxi-acetylene flame by using required pressure.Heat treatment:47

The process involving heating&cooling to egt the desired properties suitable forserviceby changing the structure,composition etc.Stages of heat treament:4. Heating to the required temperature5. Holding(Soaking) at this temperature for a period of time to attainuniform temperature throughout the section.6. Cooling the steel at specified rate.

Normalizing

Existingstructure andproperties of

Existing structure and

properties are wipedout.Metal is now in acondition to receivenew structure.

Heat

steel

Quenching

Tempering

Principle of heat treatment

Hubcooling

Normalizing:

Air cooling

It is the process of heating the steel to above the upper critical temperature followed by cooling inair.NormalizingAustenite910

TemperatureO

723

Ferrite +Pearlite

Pearlite +Cemintite0.8

C% wtPurpose:5.6.7.8.

To relieve the internal stress

To refine the grain structureTo improve the machinabilityTo improve strength&toughness48

Time in hrs(Cycle time x capacity

of the furnace)222

Quenching:The process of heating the Wheels to austenite phase followed by sudden cooling of rim bywater for about 4 - 4.5 min.Purpose of hardening followed by tempering :1. To develop high hardness, wear resistance and2. To improve the strength and toughness

AusteniteHardnening910

TemperatureO

723640550

0.8

C% wt

Tempering:Process of heating the axle to a temperature below lower critical temperature followed by aircooling.Purpose:5.6.7.8.

To reduce the thermal stress

To stabilize the structure of the axleTo reduce the brittleness andTo increase the toughness&ductibility.

49

Austenite910

TemperatureO

723640

Tempering

550

0.8

C% wt

Temperature&time of TF:ZonesPre heatingMain heatingSoaking

Temperature in o CRequiredSet550-640610610-640610610-640610

Time (Cycle time x capacity of the

furnace)2 hrs 55 min.2 hrs 55 min.2 hrs 55 min

Hub cooling:Cool the hub by the mixture of air&water for about 2.5 minutes.Air cooling:After complition of the heat treatment allow the wheels to air cool.Apex gring;Remove pins on the apex of the wheel by apex grinding machine about one full rotation.Steel shot blasting;Remove oil,crease,dirt,sand grains,spray particles and othe inclusions by steel shot blasting in aclosed chamber.Magnaglow:Do visual inspection followed by spraying the magnaglow bath on the magnetized wheel andinspect und UV lamp.If free from any defects stock the wheel as first line stock otherwise sendthe wheel containing defects to the grinding line and reinspect.Ultrasonic testing:Evaluate the quality of the rim portion of the wheel by detecting the discontinuities which areharmful to service by automatic immersion technique in a water tank by radially & axially byusing 5&2 MHz convergent beam probes of six numbers respectively(3 for axile&other 3 forradial).The wheel containg 3.2 diameter flaw ore shall be the cause for rejection.50

Brinel Hardness testing:

Remove the scale on the front rim by automatic grinding machine and measure the BHN bygiving indentation by 10 mm hardened steel ball with the load 30000 kgs.Warpage:Check the warpage of the wheel on the drag side to prevent the derailment of the wheel.Wheel peening:Peen the wheel in a closed chamber by steel shots of SAE-550 grade or equivalent to improve thefatigue strength of the wheel,to weldup the HLCs on the surface,distribute the locked up streesuniformely through the wheel.Hub bore:Make the hub bore to the required diameter by Hub borer.Final inspection:Measure all dimensions of the wheels,rotundity,circumference and others by using suitablemeasuring gauges and record the weight of the stocked wheel also.

Heat treatment of wheel:

The process involving heating&cooling to egt the desired properties suitable forserviceby changing the structure,composition etc.Stages of heat treament:7. Heating to the required temperature8. Holding(Soaking) at this temperature for a period of time to attainuniform temperature throughout the section.9. Cooling the steel at specified rate.

Normalizing

Existingstructure andproperties of

steel

Heat

Existing structure and

properties are wipedout.Metal is now in acondition to receivenew structure.Quenching

Tempering

Principle of heat treatment

Normalizing:

Hubcooling

Air cooling

51

It is the process of heating the steel to above the upper critical temperature followed by cooling inair.NormalizingAustenite910

TemperatureO

723

Ferrite +Pearlite

Pearlite +Cemintite0.8

C% wtPurpose:9. To relieve the internal stress10. To refine the grain structure11. To improve the machinability12. To improve strength&toughness

Time in hrs(Cycle time x capacity

of the furnace)222

Quenching:The process of heating the Wheels to austenite phase followed by sudden cooling of rim bywater for about 4 - 4.5 min.Purpose of hardening followed by tempering :3. To develop high hardness, wear resistance and4. To improve the strength and toughness

AusteniteHardnening910

Temperature52

723640550

0.8

C% wt

Tempering:Process of heating the axle to a temperature below lower critical temperature followed by aircooling.Purpose:9.10.11.12.

To reduce the thermal stress

To stabilize the structure of the axleTo reduce the brittleness andTo increase the toughness&ductibility.

Austenite910

TemperatureO

723640

Tempering

550

0.8

C% wt

Temperature&time of TF:ZonesPre heatingMain heatingSoaking

Temperature in o CRequiredSet550-640610610-640610610-640610

Time (Cycle time x capacity of the

furnace)2 hrs 55 min.2 hrs 55 min.2 hrs 55 min

53

Hub cooling:Cool the hub by the mixture of air&water for about 2.5 minutes.Air cooling:After complition of the heat treatment allow the wheels to air cool.

Preparation of coated sand:

54

Poring rate:Fast pouring rate:The flow of molten metal from the ladle in to the clay graphite head through ceramic pouringtube is cast fast pouring rate.Controlled pouring rate:The flow of molten metal from the clay graphite stopper head through the wheel profile in to theprobe sensor in the riser is called as controlled flow rate.The Pouring rate is given by the formulaTimePouring rate

Sec / PSI and can be read from the Anger-Gein chart

Pressureplotted by time in second in Y axis and pressure in PSI in X axis.The X axis is calibrated as onedivision is one PSI and the time in Y axis is 2.5 minutes.It shall be 2.25 1.25 Sec / PSI.Eg)The graph for the following values of time&pressure is as follows.Time in seconds2.557.510

Pressure in Pounds per Square Inch

1.63.24.86

10Pouring rate

=6=

1.67 Sec / PSI.

Flow rate diagram

12108Time in Sec.64201.6

3.2

4.8

Pressure in PSI

55

Effect of pouring rate during wheel casting:

High pouring rate: Porosity,gas holes,pin holes,cavity may form in the rim and below sprue portions If the temperature is low flow rate may sufficiently increase to prevent the cold defectsLow pouring rate: Low pouring rate may leads to cold defects like LAP If the pouring temperature is high then low pouring rate is pemitted If the bath temperature is low pouring rate may lead to cold defects.

Use of graphite moulds for wheel casting:

It has sufficient permeability It has high thermal shock It is easly machinable It may re use after casting of one wheel for further casting It has low thermal expansion It has low linearity of coefficient It has low ash content It is less volatile The chemical reaction between it and the molten metal bath is negligible After casting easily cleanable without damage for further use This is non-destructive mould Less heat / thermal loss The spray solution will easily adhere on the surface It has sufficient strength. It has high electric resistance Repairable by machining

Sand testing:GFN determination:Take 100 gms of washed,dried and any other foreign material free sand and poured in the top ofthe clean pre weighed test sieve series contains 600,425,300,212,150,106,75,53 micron sievesand pan from top to bottom.Shake well for about 5 minutes by the sieve shaker motor and takethe final weight.Findout the % of the retention in each sieves and find out the GFN of the sand asfollows

Sieve size

600425300212150100

InitialFinalWeight of % of the Factorweight of weight of theretentionthe sievethe seieveretention2030405070100

Product

56

7553Pan

140200270TotalWeight of the product

GFN

AFS.Retention

Stick point determination(SP):

Spred thin layer of coated sand using metal feeder on the stick point apparatus.After one minutebrush out the un-sticking sand by camel hair brush to the point where sand has stuck to the barfrom the lower gradient side.Immediately measure the temperature by using the thermocouple atthe point where the sand has stuck.Determination of CTS:Make the test samples by pouring the coated sand on the brequtte shape on the bottom of theheater at 232+/- 5 oC using aluminium scoop.flatten immediately and place the top heater on theleveled surface.Soak for four minutes and remove the heater.After air cooling find out the CTSvalue from the outermost scale(with the help of the movable magnet).Average of six samples willbe the CTS value of the coated sand.Determination of HTS:Pour the sample on the slot of brequtte shape of the bottom of the heater,flatten and immediatelyplace the heater overit.Bake 4 mintes and apply the load and read out the HTS value afterbreaking the sample in hot condition.Average of the two samples will be the HTS value of thecoated sand.

57

Estimation of SiO2(Ram. mass):

Take 0.5 gm of dry sample in a beaker add 50 ml of 1:1 HCL and bake. It completelyExtract with1;1 Hcl and wash thoroughly.Warm,cool and filter through 41 No. fiter paper.Take the ppt in a Ptcrucible ,chara and heat to 950 oC for about 30 minutes.9Filterate for the determination ofCaO&MgO)Cool,moisten with conc.H2SO4 and add sufficient quantity of HF and evaporate on a hotplate.Heat to 950 o c for 15 min,cool and weigh.

Wt before HFT

After HFT

SiO2 =

x 100Wt of the sample taken

Estimation of CaO:Makeup the above filterate in to 250 ml in a SM flak.Pipette out 25 ml in a conical flask,add 10ml NaOH(10 N).Make up the volume in to 50 ml,add 0.2 - 0.4 gm of P&R indicator & titrate Vs0.02M EDTA soltion(7.44 gms in one litre of water).The end point is the appearance of the violetblue colour.Note the volume of EDTA.

Vol. Of K2Cr2O7 consumed

Determination of Al2O3 in HA70% bricks:

Take 0.2-0.3gm sample and fuse with the fusion mixture at 950 deg. C & extract with 1:1Hcl..Fllter through 41 No. filter paper and make it in to 250 ml in a SM flask.Transfer 25ml ofthe aliquot and add sufficient amount of 0.01M EDTA (1 ml = 1.25gm of alumina)Add 2-3drops of methyl orange and dilute with NH4OH(1:10) drop wise till the colour change toyellow.Add 5ml acetate sodium acetate buffer(2ml acetic acid&21.5gm sodium acetate in 1 litreof dis. Water-PH 5.2),25ml water and heat toboilingfor 5 minutes.Cool and add 5-6 ml of xynolorange indicator(0.1gm in 100ml dis. Water with 2 drops of 1:1 HCl) and titrate against standardZinc Acetate solution till the colour changes from yellow to orange or pink.Add 10ml ofammonium fluoride solution and heat to boiling for 5 minutes.Cool and add 5ml buffer and 5-6drops of zylenol orange indicator and titrate against standard Zinc Acetate solution till the colourchanges from yellow to pink.

Vol. of ZnAc consumed x 1.25

Al2O3

x 100Wt of aliquot

Alumina in Fe-Si:Take 2.5gm in a Pt crucible and dissolve in 1:2 HF + HNO3 acid mixture till the samplesdsolved.Add 5ml of 50% Conc.HCl & fume till dense fumes evolved.Extract with 50ml of waterin 250ml beaker.Add 5ml of conc.hcl,boil then add 10gm of NH4cl,boil,cool and add NH2oHand again boil till faint smell of NH3 persists.Filter through 41 No. filter paper,wash with hotwater and transfer the ppt in to 250ml beaker.Add 15ml conc.HNO3 +15ml conc.perchloricacid.Fume to syrupy state with beaker covered with watch glass.Cool,add a drop of hcl,dilute to20ml,boil and add50_60ml of 10% NaOH solution,boil on low heat,cool,filter through 41 filterpaper.Wash with hot water,collect the filtrate in to beaker,Add xynol orange indicator.Add hcl tillit turns from blue to yellow.Cool,make upto 250ml.Take an aloquot of 100ml,add 20ml of0.01MEDTA,neutralize with 5% NaOH.Then add 5-10ml of acetate buffer.Boilfor10minutes,cool,add xynol orange buffer and titrate against 0.01 M Zinc sulphate.Carryout the blank with the same amount of EDTA and other reagents used above.

(Vol. of Zn Ac consumed for blank-Vol. of Zn Ac consumed for sample)

Al%

x 0.027Wt of sample in the aliquot

Estimation of Silicon in Fe-Mn:

Take 1gm sample and dissolve in 30% conc.Nitric acid in a hot plate.Dry&bake for 1 hr at 100110 deg.C.Redissolve the baked mass in 40ml conc.Hcl by warming and dilute to 150ml with hotwater.Allow to settle and filter through 40 filter paper,wash 10-12 times alternatively with hot1:20 Hcl and hot water.Ignite the ppt at 950 deg. C for about 30 minutes,cool and weigh.

59

Wt of silica obtainedSi

x 46.72Wt of sample taken in gm.

Estimation of Mn:Take the filtrate obtained after removal of silica in a 500 ml conical flask andtreat with 10ml conc.Sulphuric acid and evaporate to fumes.Cool&dilute in to 100m.Boil until allsalts get dissolved.Make up in to 500ml.Pipetted out 25ml,add small amount of Zinc Oxideemulsion till the liquid suddenly coagulates.Dilute to 200ml,boil and add 2-3 drops of conc.nitricacid and titrate vs 0.1 N KmnO4 solution in hot condition itself.Agitate the contents in a conicalflask after each addition of 0.1 N KmnO4 and allow the ppt to settle and continue to titrate till thesupernatent liquid shows pink tinge.Take two such piolet readings so that in the 3rd titration allpermanganate required can be added rapidly and the end point is noted.

Vol.Std KmnO4 consumed x Nor. Of KmnO4

Mn%

x 1.666Wt in gm of the sample in the aliquot.

Estimation of Mn in Al star:Dissolve 1gm sample in 3ml of acid mixture(Con.Sil.acid90ml +Conc.Nitric acid 50ml + Conc.Phopouric acid 95ml + Dis. Water 765ml).Dissolve an accurately weighed sample of std steelcontaining a known conc. Of Mn in 30ml of acid miture.Boil,cool and dilute to 100ml withboiling water.Add 10ml of silver nitate solution and 30ml of 10% ammo.per-sulphatesolution.Heat till permanganic acid colour is obtained.Cool the solution to room temperature add10ml of NaCl solution to pptAgCl.Titrate quickly the permanganic acid with std. Sod.Arsenitesolution until the pink colour disappears.

Vol. of std. Sodium Arsenite solution consumed

Mn%

x (A x B) / CWt. Of the sample taken

Where,ABC

===

% of Mn in std steel sample

Wt of saple taken andVol. of std arsenite solution used for titration.

Settling test: Fused silica poeder in water with the suspensions CMC&Veegum Weigh 315gm of fused silic powder,0.315gm of CMC(0.1% of FSP)&1.575gm ofveegum(1% of FSP) in 2 pockects each containing 1.575gm Dissolve CMC in 53ml distilled water& stir with mechanical stirrer for about 4 minutes Repeat the same for both the pockets of veegum in a seprate beakers.60

Take 432ml of distilled water in 1 litre measuring jar and add CMC& stir 4 minutes.Repeat the same for the two pockets of vegum.Add 315gm of FSP and stir for 4 minutes.Keep it for 24 hrs and oserve any sttling take plac e or not.

Specific gravity of FSP:

Take the empty wt of clean,dry pyknometerw1 Fill with water and weigh-w2 Pour out the water and filled with 1/ of FSP&weigh-w2 Fill with water and weigh-w4

(w3-w1)Specific gravity =(w3-w1)-(w4-w2)

61

Parts of the wheel:

Cope side:-

FlangeFront rimRiser pad

Sprue

Front hub face

Back hub face

Hub boreBack hub filletBack plateBack rim

62

Fracture toughness:Eventhough the charpy&Impact tests have certain importants they are not consideringfor engineering design.LEFM is used for the design problems.Fracture toughness isone of the material properties like yield strees and used in designs.It is defnied as theresistance of the material to resists fracture starting from the preexisting crack /defect.Testing of fracture toughness:Sample preparation:There are so many sample preparation method and one of the method for thepreparation of the sample as per ASTM,Philadelphiya STP 381133/1965 is asfollows.

Pin hole for apply load

CrackL(4w)

Slot2C or W / 3

Crack

The length of the specimen is 4 times of the width and the length of slot&crack is 1/3of the width.Load is applying through the pins in which the sample is inserted.Procedure:Do the preliminary adjustments for the Fracture Toughnes machine and insert thespecimen in to the pins.Apply the load and the material will fracture under plainstrain condition.Note the maximum load(pm ) for the calculation.

Dia 1655(Dia 1615)

Defect analysis of axle.

The distance between -

Approx. equal to OD of the nozzle

Nozzle life

1200 billets

Nozzle getting blocked due to back-firing,over used,poor quality etc

Conveyors should not move during cutting Cleen the nozzle at the beginning of each and immediately in case ofback firingReplace the slag bins and never allow bins to overflow Ensure proper seating of nozzle to torch Cutting of correct billet length Select proper billet to be cut as per the specification of R-16&43.

Ensure:Correct corner breaking during forgingCorrect 90o during corner breaking and during handoverDefect free surface on bloom and in case surface conditioning is done onbloom the width of conditioning should be 10 times the depth(8 mm ) ofthe conditioning.

Piping: Insufficient material on forged ends leading to formation of hole in thejournal end face Uneven distribution of material on both ends of ournal during forging. Poor gripping marking on jaws / work piece jerking during duringmarking Improper setting / adjustment before cutting in axle cutting machine Lack of material due to excess scale formation Ensure Correct length of billet loaded to RHw GFM programme for forging is made considering equal distribution ofmaterial for both ends GFM chuck jaws are welded properly with grip marks to avoid jerkingduring forging. Maintain correct indicator point to point distance as indicated in workinstruction.Maintain 100 to 150 mm of minimum fish end length

Ensure no ove saking of billects in RHF.In case of prolonged break

downs put off PHZ and reduced temperature to 1000 deg. C in SZ-I&II

Misfunction during forging:

Catastriphic failure of electrical or mechanical components/failure ofregular power supply leading to in complete forging Ensure Ensure machine condition with maint. Staff after PMS or after attendingto breakings. Idle cycle(without work piece) is checked in auto sequence and checkwhether all the blocks in t forging programme is correctlyexecuted.Ensure that the programme is correct and then recall the workpiece. The case of failure is to be analyzed and is best when analyzed separatelydepending on the case. In case of power interruption or failure consult MRS for regular supplyof power before starting of forging.Allow 5 minutes for supply tostabilize.

Axle drawing in Stn-1.

Face Far end

74

75

Manfacturing of BG Loco axles.

Billet cutting:Cut the fillet of 300/340 RCS of R-43/1992 bloom in to required length by Saw/Gascutting.Charging in to RHF:Charge the cut billets in to RHF and soak them at 150 1200 deg. C for about 8 hours.Forging:Forge the red hot billet at 900 1100 deg. C by 6 minutes by GFM long forgingmachine.End cutting:Remove sufficient discards by gas cut.Number stamping:Stamp the serial number of the axle on wheal seat by hot number stamping maching.Intermediate cooling:Cool the axle through the intermediate cooling bed till the surface temperature becomes200 250 deg. C.Heat treatment:Normalizing:Charge the axles into NF and soak at 860 880 deg. C for about 8 hours.Hardening;Quench the normalized hot axles by the polymer quenchant for half an hour.Tempering:Charge the quenched axles in to the TF through the intermediate cooling bed and soakat 610 660 for about 11.45 hours.Air cooling;Allow the tempered axles in to air cooling for about 36 hours.Laboratory testing:Take the lab. sample Each cast wise from the mid radius of wheel seat/journal andconduct all the required testing .Machining in AMS:End milling, centering and LCB:I f the lab test is ok load the axles in to station-1 in AMS and do the above operations atstation-1 with the surface finishing of 0.8 micron.Ultrasonic testing:Do visual examination and carryout the ultrasonic testing and if the axles are passedstamp the UT punch mark.Rough turning of axle:Do the rough of the axle in station-2 as per the dimensions mentioned in the drawing.Radial scanning of the axle.Find the longitudinal defects by USL radial scanning machine/manual body scanning.Ifthe axle pass enter the status in LAN.

Final inspection;Carryout the final inspection thoroughly and if the axle is confirming to all therequirements made the dispatch arrangements.